Ok, problem solved: My device (PCAN-USB CAN analyzer) had a different D-9 pin layout, so the CAN Hi and CAN lo pins from the shield went nowhere...
In case anybody has similar problems:
Shield Pin 3 (CAN Low) <--> PCAN Pin 2 (CAN Low)
Shield Pin 5 (CAN High)<--> PCAN Pin 7 (CAN High)
Thanks anyway!!!